Download Name: Date: ______ Instructions

Name: __________________________ Date: _____________
Instructions: Put answers on the Green Scantron Sheet. Return both the question paper and the scantron sheet.
1. Science is a body of knowledge that A) describes order in nature
C) condenses knowledge into testable laws D) All of the above
2. The SI base unit for mass is:
A) gram
B) pound
B) is an on going human activity
C) kilogram
3. Which of the following Greek Astronomers calculate the size of Earth?
C) Eratosthenes D) All of the above
D) ounce
E) kilopound
A) Pythagoras
B) Potlemy
4. The average speed of a moving object during a given interval of time is always: A) the magnitude of its average
velocity over the interval B) the distance covered during the time interval divided by the time interval C) onehalf its speed at the end of the interval D) its acceleration multiplied by the time interval E) one-half its
acceleration multiplied by the time interval.
5. A ball is in free fall. Its acceleration is: A) downward during both ascent and descent B) downward during
ascent and upward during descent C) upward during ascent and downward during descent D) upward during
both ascent and descent E) downward at all times except at the very top, when it is zero
6. A baseball is thrown vertically into the air. The acceleration of the ball at its highest point is:
down C) g, up D) 2g. down E) 2g, up
A) zero
B) g,
7. A freely falling body has a constant acceleration of 9.8 m/s2. This means that: A) the body falls 9.8 m during each
second B) the body falls 9.8 m during the first second C) the speed of the body increases by 9.8 m/s during
each second D) the acceleration of the body increases by 9.8 m/s2 during each second E) the acceleration of
the body decreases by 9.8 m/s2 during each second
8. Which of the following quantities is NOT a vector?
D) Acceleration E) Force
A) Mass
B) Displacement
9. The inertia of a body tends to cause the body to: A) speed up B) slow down
motion D) fall toward the Earth E) decelerate due to friction
10. Which one of the following is a unit for acceleration?
A) m/s
B) m/s2
C) Weight
C) resist any change in its
C) s/m D) s/m2
11. An object is thrown straight up from ground level with a speed of 50 m/s. If g = 10 m/s2 its distance above ground
level 1.0 second later is: A) 40 m B) 45 m C) 50 m D) 55 m E) 60 m
12. A car, initially at rest, travels 20 m in 4 s along a straight line with constant acceleration. The acceleration of the car
is: A) 0.4 m/s2 B) 1.3 m/s2 C) 2.5 m/s2 D) 4.9 m/s2 E) 9.8 m/s2
13. A 40 gram egg falls from rest atop a 15 meters tall tree. How long does it take to hit the ground?
C) 2.89 s D) 1.2s
A) 1.7s
B) 5s
14. A racing car traveling with constant acceleration increases its speed from 10 m/s to 30 m/s over a distance of 60 m?
How long does this take? A) 2.0 s B) 4.0 s C) 5.0 s D) 8.0 s E) The time cannot be calculated since
the speed is not constant
15. A feather and a lead ball are dropped from rest in vacuum on the Moon. The acceleration of the feather is:
A) more than that of the lead ball B) the same as that of the lead ball C) less than that of the lead ball
D) 9.8 m/s2 E) zero since it floats in a vacuum
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16. The block shown moves with constant velocity on a horizontal surface. Two of the forces on it are shown. A
frictional force exerted by the surface is the only other horizontal force on the block. The frictional force is:
A)
B)
C)
D)
E)
0
2 N, leftward
2 N, rightward
slightly more than 2 N, leftward
slightly less than 2 N, leftward
17. A bullet shot horizontally from a gun: A) strikes the ground much later than one dropped vertically from the
same point at the same instant B) never strikes the ground C) strikes the ground at approximately the same
time as one dropped vertically from the same point at the same instant D) travels in a straight line E) strikes
the ground much sooner than one dropped from the same point at the same instant
18. A boy on the edge of a vertical cliff 20 m high throws a stone horizontally outwards with a speed of 20 m/s. It
strikes the ground at what horizontal distance from the foot of the cliff? Use g = 10 m/s2 A) 10 m B) 40 m
C) 50 m
D) 50 5 m
E) none of these
19. A box with a weight of 50 N rests on a horizontal surface. A person pulls horizontally on it with a force of 10 N and
it does not move. To start it moving, a second person pulls vertically upward on the box. If the coefficient of static
friction is 0.4, what is the smallest vertical force for which the box moves?
A)
B)
C)
D)
E)
4N
10 N
14 N
25 N
35 N
20. Which of the following is the most correct expression for Newton's Second Law
C) f  m / a
D)

F  ma net
A)
F  ma
B)


Fnet  ma
21. Part II Question I: You are allowed to use your textbook. You must show all relevant detail work to get full or
partial credit for this problem. Use the space below to show your final work. Do scratch work somewhere else.
Object 1 is thrown up with a velocity v and object 2 is thrown up with velocity 3v. Find the maximum height of
object 2 in terms of the maximum height of object 1,
h 
i.e  2  .
 h1 
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22. Part II Question 2. You are a substitute teacher for a middle school and your are called by the principle to substitute
an 8th grade science class for a teacher who has taken ill. You are asked to cover material that will introduce the
students to the work of Gallileo Gallilee on the law of falling bodies. The class teacher has informed you that she
already covered, speed velocity and acceleration in the previous week. The teacher suggest that you want to teach
this material by showing a demonstration in which several nuts are tied to the string at specific distance and falling
on a tin pan. To do this you develop an activity in which students will participate by providing answers. The
questions of this activity are given below. You are to answer the questions as if you were a student watching the
demonstration.
You ask the student to do this with you:
What happens when you drop a pen and a paper from the same height? Explain your observations.
You ask the student to do this with you:
Now crumple the paper into a small ball and drop it again with the pen from the same height. What is the difference
now?
Demonstration
Tie the first nuts to one end of the string and the second at a distance d = 5 cm from the first nut. Tie three more at
the same distance d from the previous nut. Hold the string straight up so that the first nut just touches the pan. Drop
the string and listen fro the "clangs" carefully.
You ask the students: You also repeat the demo couple of times for the slow ones to catch up.
Do the clangs occur at equal time intervals? How would you write this in terms of a relationship between distance
interval of the nuts d and time t between each clang.
Demonstration
Now Tie the first nuts to one end of the string and the second at a distance d = 5 cm from the first nut. Tie three
more at the distance 4d, 9d and 16d. Hold the string straight up so that the first nut just touches the pan. Drop the
string and listen for the "clangs" carefully.
You ask the students: You also repeat the demo couple of times for the slow ones to catch up.
Do the clangs occur at equal time intervals? How would you write this in terms of a relationship between distance
interval of the nuts d and time t between each clang.
After the demonstration you explain to the class that Gallileo reasoned from such an experiment that all objects no
matter what, fall to the ground such that d 
1 2
gt , where g (`~10 m/s2) is a constant provided one condition is
2
met. What is this condition?
After the class two students come up to you and ask a question. How can you show from this experiment that g~10
m/s2? Formulate the response to this question by showing how to calculate the value of g from the experimental
data.
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Answer Key
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
D
C
C
B
A
B
C
A
C
B
B
C
A
B
B
B
C
B
D
B
Given v1i  v, v2i  3v
Let h1 and h2 be the maximum heights
We Know that v1 f  0 and v2 f  0 at maximum height
21.
v12f  v12i  2ah1  1
v22 f  v22i  2ah2   2 
Divide  2  by 1
h v 2  3v 
 2  22i  2  9  h2  9h1
h1 v1i
v
2
22.
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